Renderers available: Software, OpenGL, Vulkan.Based on the same code as ZDoom, except it also uses an OpenGL and Vulkan renderer. Nearly every mod should work with GZDoom, specifically ones that use special effects.

Renderers available: Software, OpenGL.Limit-removing source port based off Boom that aims to preserve the feel of vanilla Doom while adding modern editing features. Includes an OpenGL renderer and supports high resolutions.

Renderers available: Software.A source port that aims to accurately reproduce the experience of playing vanilla Doom. Renders at a low-resolution (that's upscaled to higher resolutions) and purposefully keeps the original game's limits.

Renderers available: Software (with acceleration), Direct3D, OpenGL. Source port based off Chocolate Doom that supports vanilla, limit-removing and Boom-compatible maps and makes a few other changes/fixes for the modern age while still keeping the classic Doom experience.